In Yu-Gi-Oh! anime, Obelisk the Tormentor is the god of light and dark. The Obelisk card is one of three Egyptian Gods and because of the power associated with it, there are very specific and arcane rules for using the card. The OCG, or Official Card Game rules are created and maintained by Konami.
To use Obelisk the Tormentor, you must tribute, that is, release three other monster cards to invoke a Normal Summon. Obelisk can also return from the discarded card pile via a Special Summons. The Special Summons places Obelisk back under the control of the owner. After the turn is played, the Obelisk card must be returned to the Graveyard. If Obelisk is in the Graveyard in a defense position when the owning player is attacked, the card can be used as a shield for other monsters.
Obelisk cannot be returned to your hand after it has been used but retains many abilities from the Graveyard, or pile of used cards. There is no force in the Yu-Gi-Oh! official card game that can remove Obelisk from play. In addition, Obelisk must be used as is and cannot be enhanced by Equip cards. Fortunately, the attack and defense powers of the Obelisk make Equip cards unnecessary.
Protections and Defenses
According to the OCG, Konami's official card game rules, Obelisk the Tormentor can be affected by spells and traps but the effect doesn't last long, extending only to the End Phase, or the last step of your opponent's turn. When you place Obelisk the Tormentor face up on your playing field, it is impervious to destruction via card effects.
Each time you want to use Obelisk the Tormentor in an attack, you have to discard, or tribute, two monsters in your deck. Obelisk has the ability to attack any and all of your opponent's monsters. With the card, you also have the ability to augment the attacking power of Obelisk to infinity. The cost of this power is two of your other monsters but the result to your opponent is the destruction of all of her cards.